Final answer:
The functions that could be graphed based on the given domain are a, b, c, and d.
Step-by-step explanation:
To determine which functions could be graphed based on the given domain, we need to consider the restrictions on x for each function.
a. f(x) = x² can be any real number, so it satisfies the given domain.
b. g(x) = √x has a restriction that x must be greater than or equal to 0. This satisfies the given domain.
c. h(x) = 1/x has a restriction that x must be not equal to 0. This also satisfies the given domain.
d. k(x) = sin(x) can be any real number, so it satisfies the given domain.
Therefore, the functions that could be the one graphed are a, b, c, and d. The correct answer is option A.