Co-efficient of `alpha^t` in thet expansion of `(alpha+p)^(m-1)+(alpha+p)^(m-2)(alpha+q)+(alpha+p)^(m-3)(alpha+q)^2+dot(alpha+q)^(m-1)` where `alpha != -q and p !=q` is :
A. `(.^(m)C_(t)(p^(t) - q^(t)))/(p-q)`
B. `(.^(m)C_(t)(p^(m-t) - q^(m-t)))/(p-q)
C. `(.^(m)C_(t)(p^(t) - q^(t)))/(p-q)`
D. `(.^(m)C_(t)(p^(m-t) + q^(m-t)))/(p-q)`
