$\begin{array}{1 1} \text{(a) In case of mercury and glass, we observe a convex meniscus} \\ \text{
(b) Surface tension is responsible for the rise and fall of the capillary tubes} \\ \text{
(c) If two drops encounter each other, they tend to repel each other} \\ \text{
(d) All of the mentioned}
\end{array} $