We know from the triangle inequality that the last side, $s$, fulfills $s+18\textgreater25$. Therefore, $P\textgreater25+25$. The least integer value of $P$ is $51$ 
For $\triangle ABC$, all its side lengths are integers. The perimeter of $\triangle ABC$ with a side of length $25$ and a side length of $18$ is at least ． 

a) $$25$$ 
b) $$18$$ 
c) $$52$$ 
d) $$51$$ 
e) $$50$$ 