Logical Breakdown
To solve this triple-blank sentence, we must look for the cause-and-effect chain established by the words "such... that" and "indeed."
1. The "Indeed" Bridge (Blank iii): The second half of the sentence says: "...we would expect $\([\mathrm{X}]\)$, and, indeed, we find $\([\mathrm{Y}]\)$." The word "indeed" confirms that our expectation was correct. If we find that these clocks are ubiquitous (found everywhere), it confirms an expectation that most organisms would have them. Unknown (H) or compulsory (I) would not logically follow an expectation of general presence.
2. The Expectation (Blank ii):

If biological clocks are found everywhere (ubiquitous), what was our expectation? It was that most organisms would possess (have) them. Eschew (D) means to avoid, which contradicts the "indeed" finding, and select (F) implies a conscious choice or a specific evolutionary process that is less direct than simply "having" the trait.
3. The Value (Blank i):

Why would we expect organisms to possess these clocks? Because they have clear adaptive value. In GRE logic, if something is "ubiquitous" in nature, it is usually because its benefit is obvious or significant. Meager (A) means small/weak, and ambivalent (B) means having mixed feelings/uncertain value-neither would lead to the conclusion that "most organisms" should have them.