The correct option is B 2(m+5)(m+5)
Given, the expression is
2m2+20m+50.
=2[m2+10m+25] ...(i)
Now, comparing the expression m2+10m+25 with the identity x2+(a+b)x+ab
We note that,
(a+b)=10 and ab=25
So,
(5+5)=10 and (5)(5)=25
Hence,
m2+10m+25
=m2+5m+5m+25
=m(m+5)+5(m+5)
=(m+5)(m+5)
Now from (i), we get
2m2+20m+50=2(m+5)(m+5)