Answer:
Correct is B.
Step-by-step explanation:
The question is incomplete, the options are attached to the graph and the request is answered
According to the exercise, we can help the researcher to look for other additional data such as: if the size of the proboscide is so influential as to attract more couples and this intervenes in the number of individuals with a large proboscide, therefore the correct answer is the "B", option A is discarded because the relationship of the size of the body with that of the proboscis is not relevant to the matter to be investigated, option "C" is discarded, because the fact of whether it is inheritable or not Tube size is not in doubt and option "D" is ruled out because we are not studying the population size of this species.