Milk protein (Casein) $\overset{Rennin\ }{\rightarrow}\ \begin{matrix}
(A) \\
\ \ Paracaesin\ \overset{Ca^{2 +}(B)}{\rightarrow}
\end{matrix}$ calcium paracaseinate $\overset{Pepsin}{\rightarrow}$ Peptones (C) Enzyme rennin is prominent in the stomach of infants, while both pepsin and rennin are absent in invertebrates