Let Jason's salary be x in 1995 and Karen's salary be y in 1995.
So in 1998 their respective salaries were x+(xp/100) and y+(yp/100) or x(100+p)/100 and y(100+p)/100.
The question is asking for the value of p.
First consider statement (1) alone.
It means y-x = 2000.
Since nothing is being said about p, this information is not sufficient to answer the question.
Next consider statement (2) alone.
It means y(100+p)/100 - x(100+p)/100 = 2440 or {(100+p)/100}*(y-x) = 2440.
Again this information alone is not sufficient to answer the question.
Next combine both the statements together and check.
So we get two equations.
y-x = 2000.
and {(100+p)/100}*(y-x) = 2440.
On dividing second equation by first one we get (100+p)/100 = 2440/2000.
Or 100+p = 122 or p = 22.
So both statements together are sufficient to answer the question.
The correct answer is hence (C).