by JonathanSchneider Thu Nov 06, 2008 1:51 pm
I wouldn't stress too much about the particularities of non-GMAC problems. The reason we stress that you study from the OG is that these problems have undergone intense scrutiny from the GMAC board before being used on actual tests. Questions from other sources do not undergo the same scrutiny. As a result, you may end up splitting hairs that ought not be split.
Nevertheless, the answer is D. The word "and" here reuiqres parallelism. What must be parallel? The two modified nouns: "sensible exercise" and "proper diet."
Between B and D, go with D to keep your tenses consistent (no reason to switch to the past tense here).