The correct options are
C 10
D -10
When you compare the given equation to the standard form ax2+bx+c=0 we get,
a=1,b=p and c=25
Given that , the roots of the equation are real and equal.
i.e. , D = 0
⇒D=b2−4ac=p2−(4×1×25)=0
⇒p2−100=0
⇒p2=100
∴p=10 or −10