Question

Comprehension: In the following passage, some words have been deleted. Read the passage carefully and select the most appropriate option to fill in each blank. Deoxyribonucleic acid (DNA) is a very special molecule. It (1)__________________ as the code for all life on Earth, holding the cellular instructions to (2)______________ everything from a beetle to a human. Because DNA is (3)_________________ to each species, it’s like a product barcode in a supermarket. As animals and plants live their lives, they (4)________________ fragments of their DNA into their environment (5)_________________ dead skin, hair, saliva, scat, leaves or pollen. These traces make up environmental DNA. There’s enough DNA in water and even air to tell species apart. Select the most appropriate option to fill in blank no. 5.

• A. above
• B. farther
• C. through
• D. for

Answer 1

Answer:

C. through

• 1. Context of the Sentence: The passage states: "...they (4) shed fragments of their DNA into their environment (5)_________________ dead skin, hair, saliva, scat, leaves or pollen." 2. Why 'through' is the answer: Mechanism/Medium: In this sentence, the word "through" is used to show the medium or the means by which the DNA enters the environment. The Process: DNA doesn't just float away on its own; it travels via or by means of the skin, hair, and leaves. Therefore, "through" correctly connects the act of shedding to the specific biological materials being lost. Usage: It indicates that these fragments (skin, hair, etc.) are the "carriers" of the DNA.