23. (B)
Question Type: Inference
This question is somewhat unusual in that it asks to choose something that must be false on the basis of the facts given. That means the wrong answer choices will all be "must be true" or "could be true" statements. (As it turns out, they all could be true; there’s nothing in the argument that necessitates them, but nothing that rules them out, either.) We’re told that taxi drivers work fewer hours when they’re busy, because they reach their target income more quickly. That means the length of their workday varies inversely as their effective hourly income, directly contradicting the notion that people will work longer when their effective hourly wage is higher. So (B) is correct.
Side note: this is one of the out-of-scopiest LR problems ever devised:
(A) is out of scope. The author doesn’t address financial needs. An income target is not necessarily related to needs.
(C) is out of scope. There’s nothing here about any tradeoff between wages and scheduling freedom.
(D) is out of scope. Nowhere is standard of living mentioned.
(E) is out of scope! The author doesn’t say anything about efficiency.