Three positive numbers $p, q, r$ are in HP, $(r > p)$, then $log (p+r) + log (p-2q+r)$ is equal to

Question

$(a)\;2\;log\;(r-q)\qquad(b)\;2\;log\;(p+r)\qquad(c)\;2\;log\;(r-p)\qquad(d)\;log\;pqr$