This is a commonly acknowledged problem with the English word 'or'; sometimes we genuinely mean what computer scientists and logicians call an 'exclusive or' (in this question: physics *or* english, but *not* both), and sometimes we mean an 'inclusive or' (in this question: physics, or english, or both). Because the word can be ambiguous, a real GMAT question will always make clear which meaning is intended. The wording of test prep company questions is not always as precise as the real thing, as is clearly the case here.

In either case, cramya's solutions are perfect- knowing the correct answer, it's clear the question writer intended to ask 'what percent take either physics or english or both', and hence the answer is approximately 47%. Still, I take issue with the question in another respect: the correct answer is clearly not 47%, but is instead 46.666...%. If this were a real GMAT question, the question would make clear that the answers are approximations, and not exact values.

So the question, if it is accurately quoted, is not well written for two different reasons- the answers are only approximate, and the use of 'or' is ambiguous.