The members of the frame shown below have the flexural rigidities as shown and each is of length L. If a moment M is applied at Joint B, then the rotation of this joint B is
1
\(\frac{{ML}}{{12EI}}\)
2
\(\frac{{ML}}{{11EI}}\)
3
\(\frac{{ML}}{{8EI}}\)
4
\(\frac{{ML}}{{7EI}}\)