Designed to identify new compounds with antibiotic properties in extreme environments, ______ involved collecting microbial samples from thermal vents...

Let's begin by understanding the meaning of this sentence. We'll use our understanding of pause points and segment the sentence as shown - understanding and assimilating the meaning of each segment bit by bit!

Sentence Structure

• Designed to identify new compounds
  • with antibiotic properties
    • in extreme environments,
• [?]
  • involved collecting microbial samples
    • from thermal vents
      • in Yellowstone National Park.

• The analysis
  • revealed three previously unknown bacterial species
    • with promising pharmaceutical applications.

Understanding the Meaning

Let's start reading from the beginning:

'Designed to identify new compounds with antibiotic properties in extreme environments,'

This opening phrase is telling us the PURPOSE of something:

• Something was designed (created/planned)
• Its goal was to identify new compounds
• Specifically compounds with antibiotic properties
• Found in extreme environments

This is where we have the blank. Let's look at the choices:

• A. biochemist Dr. Maria Chen's investigation
• B. microbial samples from thermal vents were collected and the work
• C. the collection of microbial samples from thermal vents
• D. a research project funded by the National Science Foundation

To see what works here, let's read the rest of the sentence and understand what it's saying!

The sentence continues: 'involved collecting microbial samples from thermal vents in Yellowstone National Park.'

So whatever fills the blank:

• was designed to identify new antibiotic compounds
• AND involved collecting microbial samples from Yellowstone

The second sentence adds: 'The analysis revealed three previously unknown bacterial species with promising pharmaceutical applications.'

This confirms we're talking about a scientific research study.

What do we notice about the structure here?

The opening phrase 'Designed to identify new compounds...' is a MODIFIER - it's describing whatever comes right after the comma.

• In English, when you start with a describing phrase followed by a comma,
  • that phrase must logically describe the noun that comes right after

• So we need to ask: What can logically be "designed to identify" compounds?

Let's think through the choices:

• Can microbial samples be "designed to identify" something?
  • No - samples don't identify things; they're what you collect

• Can "the collection" be designed?
  • Awkward - plus it creates redundancy ("collection... involved collecting")

• Can a biochemist's investigation be designed?
  • Awkward phrasing - investigations are conducted, not designed

• Can a research project be designed?
  • YES! Research projects ARE designed with specific purposes

So we need Choice D: "a research project funded by the National Science Foundation"

This makes perfect sense: A research project can be designed to identify compounds, and a research project involves collecting samples.

GRAMMAR CONCEPT APPLIED

Introductory Modifying Phrases Must Match What Follows

When a sentence begins with a descriptive phrase followed by a comma, that phrase must logically describe the noun that comes immediately after the comma. This is sometimes called a dangling modifier error (in grammar terms) when done incorrectly.

The Pattern:

• [Modifying phrase], [noun being modified] [rest of sentence]

Examples:

✓ Correct: "Designed to reduce energy costs, the new building features solar panels."

• "The new building" can logically be "designed" → makes sense

✗ Incorrect: "Designed to reduce energy costs, solar panels were installed in the new building."

• "Solar panels" cannot be "designed to reduce energy costs" (the building was designed; the panels were just part of it) → doesn't make logical sense

✓ Correct: "Hoping to improve test scores, the teacher created extra study sessions."

• "The teacher" can logically be "hoping" → makes sense

✗ Incorrect: "Hoping to improve test scores, extra study sessions were created."

• "Extra study sessions" cannot be "hoping" → doesn't make logical sense

In this question:

• The opening phrase "Designed to identify new compounds..." must describe something that can logically be "designed"
• Only "a research project" fits this requirement
• Research projects are things that ARE designed with specific purposes, making this the logical match