Question

researchers can genetically select lettuce crops to cultivate for pest resistance. one of the concerns scientists have about genetically selected crops is that some traits for pest resistance may affect the texture of lettuce.

what question could be asked to begin this investigation by looking at a measurable dependent variable?
what is the effect of crop selection for pest resistance on the distribution of leaf size in a population of plants?
what is the effect of crop selection for pest resistance on the toughness of lettuce leaves?
what is the effect of crop selection for pest resistance on the sale of green salad in grocery stores?
what is the effect of crop selection for pest resistance on the texture most preferred for consumption by grasshoppers?
done

Explanation:

To determine the correct question, we analyze the dependent variable (texture - related, measurable).

• Option 1: Leaf size distribution is not directly about texture.
• Option 2: Toughness of lettuce leaves is a measurable aspect of texture, related to the concern about how pest - resistance traits affect lettuce texture.
• Option 3: Sale of green salad in grocery stores is not related to lettuce texture (it's about market sales, not the lettuce's physical property).
• Option 4: Texture preferred by grasshoppers is about pest preference, not the lettuce's texture for the investigation's context (the concern is about lettuce's texture, not pest's preference for texture).

Answer:

B. What is the effect of crop selection for pest resistance on the toughness of lettuce leaves?