Answer:
Option B
Explanation:
$\frac{1}{\log_{xy}{xyz}}+\frac{1}{\log_{yz}{xyz}}+\frac{1}{\log_{zx}{xyz}}$
= $\log_{xyz}{xy}+\log_{xyz}{yz}+\log_{xyz}{zx}$
=$ \log_{xyz}{xy\times yz\times zx}$
=$\log_{xyz}{(xyz)^{2}}$
=$2\log_{xyz}{xyz}$
=2\times 1
=2