So, imagine you had some substance in a bowl. The bowl has a little wall going through the middle, with no openings or anything.
On one side of the wall, there are 100 molecules of the supstance. On the other, there are 10 molecules.
Now, imagine that you make an opening in that little wall that separates the substance into two parts.
Normally, the 100 molecules would start pouring into the part with 10 molecules, or “go down the concentration gradient”, which means going from the part with higher concentration into lower until they are equal.
Going /against/ the concentration gradient is just the opposite — if the 10 molecules went into the side with 100, which takes energy to do.
A primary source offers a firsthand account of an event.
As Bookworm83 pointed out already, C nor D couldn't possibly correct, also due to the reason that he was able to come up with the 14 point plan. However, the real answer to your question would be A - he was very shy.
The shyness of Woodrow Wilson has been readily documented in variou sources and is also the reason why it's th ecorrect answer. Overcoming something like shyness was not an easy thing to do for him.
