You've got that p + q + r = 50 000.
1 tells us that p = 1/4(q + r), making q + r = 4p. This means that p + q + r = p + 4p = 5p = 50 000, making p = 10 000. However, without further info, you can't tell who got the least amount. q could be 5 000 and r could be 35 000 or vice versa.

2 means that r = p + q, making 2r = 50 000 or r = 25 000. Again, you can't tell which is smaller: p could be 24 000 and q 1000 or the other way around.

Put the two stmts together and you have that p is 10 000, r is 25 000 and q can only be 50 000 - 10 000 - 25 000 or 15 000. This makes p the least amount. So my answer is C