Let's break down the sentence blank by blank, looking for logical consistency and clues from the surrounding context. The overall theme is the body's metabolic response to dieting and why certain dieting strategies are ineffective.
- Blank (i): "The body's response to sharply reduced caloric intake is to slow the metabolism; contrary to what some dieters may think, though, this reaction (i) _______ as a way to aid survival, not merely as a means to (ii) _______ modern attempts at weight loss."
- The phrase "as a way to aid survival" indicates the purpose or origin of this metabolic slowing. It's a natural, adaptive process.
- "Contrary to what some dieters may think" suggests that dieters might misinterpret this reaction as something designed to thwart them.
- A. promoted: To support or actively encourage. This doesn't fit the idea of a biological reaction originating for a purpose.
- B. reiterated: To say again or repeat. This is irrelevant.
- C. evolved: Developed gradually, especially from a simple to a more complex form. This perfectly fits the idea of a biological adaptation that developed over time for survival.

So, Blank (i) is C. evolved.

- Blank (ii): "...not merely as a means to (ii) $\(\qquad\)$ modern attempts at weight loss."
- This blank describes the perceived (by dieters) purpose of the metabolic slowing. Dieters might think it's designed to frustrate or defeat their weight loss efforts.
- D. enhance: To intensify, increase, or further improve the quality, value, or extent of. This is the opposite of what dieters would perceive.
- E. foil: To prevent (something considered undesirable) from succeeding. This perfectly fits the idea of thwarting or frustrating weight loss attempts.
- F. plunder: To steal goods from (a place or person), typically using force and in a time of war or civil disorder. This is irrelevant.

So, Blank (ii) is E. foil.
- Blank (iii): "Restricting caloric intake too (iii) $\(\qquad\)$ is therefore not the best dieting strategy."
- The sentence explains that the body slows metabolism in response to "sharply reduced caloric intake." This implies that the restriction is severe. The conclusion then states that restricting intake in this manner is not the best strategy.
- G. severely: Very great; intense. This fits the idea of "sharply reduced" and explains why the strategy is not ideal (because it triggers the metabolic slowdown).
- H. ambivalently: Having mixed feelings or contradictory ideas about something or someone. This describes a state of mind, not a degree of restriction.
- I. immutably: In a way that cannot be changed. This is irrelevant.

So, Blank (iii) is G. severely.

Putting It Together:
"The body's response to sharply reduced caloric intake is to slow the metabolism; contrary to what some dieters may think, though, this reaction evolved as a way to aid survival, not merely as a means to foil modern attempts at weight loss. Restricting caloric intake too severely is therefore not the best dieting strategy."

This completed passage creates a coherent explanation of the body's metabolic defense mechanism and its implications for dieting.

The final answer is $\(\mathrm{C}, \mathrm{E}, \mathrm{G}\)$.