请教语法一题

(Princeton Review's GMAT Verbal Workout) Sample question 6.

The Johns Hopkins Center for Gun Policy and Research revealed that half of all American men keep a gun in the house, and that on any given day, one out of every fifty adults carry a handgun away from home.

A. one out of every fifty adults carry

B. every one out of fifty adults carry

C. out of every fifty adults, one carries

D. each adult among fifty carries

E. one adult in fifty carries

The correct answer is E. PRVW's explanatioin is:

C and D are incorrect because they use every and each, which suggest that if you take fifty people off the street and put them in a room,, exactly one will be carrying a handgun. But the point of the sentences is to establish a more general ratio: for every forty-nine people who don't pack heat, there is one person who does.

请教如何理解这一段话？在我看来C更像正确答案。因为D、E都会引起一个“50岁”的成人的歧义。each 和 every 在这题中有什么样的误导呢？

另外，pack heat 是什么意思？