Why is the speaker of the house second in line of the presidential succession after the?

The Speaker of the House is not second in line of Presidential succession. The second in line would be the Vice President. Then it would be Speak of the House; who is currently Paul Ryan.

The reason this happened boils down to favoritism within the Truman presidency. He proposed to change the succession in 1947 because he preferred the Speaker of the House who at the current time was Sam Rayburn over the President Pro Tempore of the Senate, Ken McKellar. 

i think its either b or c

explanation:

the award is named for an american naval historian and theorist, rear admiral alfred thayer mahan, united states navy who, through his writing, provided stimulus and guidance to those who share in the defense of the nation.