Final answer:
The hydroxide ion concentration of the lake cannot be determined without the hydronium ion concentration.
Step-by-step explanation:
The hydroxide ion concentration of the lake can be determined using the equation [H3O+][OH-] = 1.0 × 10^-14. Since the hydronium ion concentration of the lake is not given in the question, we cannot directly calculate the hydroxide ion concentration. Therefore, we cannot determine the correct option from the given choices (A, B, C, D).