Cheng Dang and her colleagues at the University of Washington recently ran simulations to determine the extent to which individual...

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

• Cheng Dang and her colleagues at the University of Washington
  • recently ran simulations
    • to determine the extent
      • to which individual snow [?] affect the amount of light
        • reflecting off a snowy surface.

Understanding the Meaning

Let's start reading:

• Cheng Dang and her colleagues at the University of Washington
  • A research team at the university

• recently ran simulations
  • They conducted computer models or tests

• to determine the extent to which...
  • Their goal was to find out how much...

Now here's where we need to fill in the blank: "individual snow ______ affect the amount of light reflecting off a snowy surface."

Let's look at our choices to see what we're deciding:

• Choice A: grain's physical properties'
• Choice B: grains' physical properties
• Choice C: grains' physical property's
• Choice D: grains physical properties

We need to figure out:

1. Is it "grain" (singular) or "grains" (plural)?
2. Where do apostrophes go (if anywhere)?

Let's think about what makes sense:

• "individual snow grains"
  • The word "individual" is describing how we're looking at snow grains - separately, one by one, not as one big clump of snow
  • We're talking about multiple grains being studied individually
  • So we need the plural: "grains"

• The verb is "affect" (plural form)
  • This confirms we need plural "grains" - if it were singular "grain," we'd need "affects"

Now, what about the possessive relationship?

• "grains' physical properties"
  • The physical properties BELONG TO the grains
  • Each grain has properties (like shape, size, texture)
  • So "grains" needs to show possession: "grains'" (apostrophe after the s for plural possessive)

• "physical properties"
  • These properties are what affect the light
  • The properties themselves don't possess anything else
  • So NO apostrophe after "properties"

So we need: grains' physical properties - the physical properties that belong to the grains.

The complete meaning is: Researchers ran computer simulations to figure out how much the physical characteristics of individual snow grains influence how light reflects off snow.

The correct answer is Choice B.

GRAMMAR CONCEPT APPLIED

Showing Possession with Plural Nouns

When you want to show that something belongs to a plural noun, you need to place the apostrophe correctly:

For plural nouns ending in 's': Add only an apostrophe after the 's'

• Multiple grains possess properties → grains' properties
• Several students' projects → students' projects
• The cars' engines → cars' engines

Important: The thing being possessed does NOT get an apostrophe (unless it also possesses something else)

• CORRECT: grains' properties (properties belong to grains)
• INCORRECT: grains' properties' (properties aren't possessing anything)

The pattern:
[plural noun] + apostrophe + [thing possessed]

In our sentence:

• grains' = plural noun with possessive apostrophe (multiple grains)
• physical properties = the thing possessed (no apostrophe because properties aren't possessing anything; they're just affecting the light)

The structure tells us that these physical properties belong to the individual snow grains, and then these properties are what affect how light reflects off the snowy surface.