Step 1: Understanding the Concept.
The passage gives a direct rule: fewer restrictions on advertising lead to more lawyers advertising. We need the option that must follow directly from the stated facts, not one that adds new, unsupported claims.
Step 2: Check option A.
The passage never claims advertising lawyers would raise prices once a specific rule is lifted; this is an unsupported guess, not a certainty.
Step 3: Check option B.
The passage talks about advertising and pricing, not about how many consumers choose to use legal services at all; this claim goes beyond what is stated.
Step 4: Check option D.
The passage never claims that non-advertising lawyers will change their own prices in response to others advertising; this is an extra, unsupported leap.
Step 5: Check option C.
Removing the fee-arrangement restriction is simply one example of “removing a restriction”, and the passage's very first sentence already states that fewer restrictions directly lead to more lawyers advertising. This option is a direct, guaranteed restatement of the given premise.
Step 6: Final Answer.
Option C must be true, since it follows straight from the stated first premise.