What do members of the same species always have in common?
a. they are always preyed upon by the same predators
b. they always occupy the same habitat at the same time
c. they always have the same number and kinds of chromosomes
d. they always occupy the same position in the food web no matter where they live

The members of the same species will always have the same number and kinds of chromosomes. So, correct option is C.

Rest of the options i.e. A, B & C may not be true for the members of the same species.

For example, if we talk about humans (Homo sapiens). All the normal human beings have 23 pairs of chromosomes out of which 22 pairs are autosomes and the 23rd pair (1 pair) is allosome that means our species will always have the same number and kinds of chromosomes. But, still we may prey upon different predators or diet. Some humans are carnivorous, some are ominovorous while others are herbivorous. We may occupy different habitat at the same time. Some of the humans live near poles whereas some live near equator that simply means that our habitat may differ.  Also, as already explained, we humans may occupy different positions in the food web. Those who eat vegan diet will be referred to as secondary consumers while those who feed upon non-vegetarian diet will occupy the position of tertiary consumers.

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