The correct option is C −−→OA=−−→OC−−−→AB−−−→BC;−−→OB=−−→OC−−−→BC;−−→CA=−−−→AB−−−→BC
OABC is a tetrahedron.
Expressing the vectors −−→OA,−−→OBand−−→CA
in terms of the vectors −−→OC,−−→ABand−−→BC
−−→OA=−−→OC+−−→CA
=−−→OC+−−→CB+−−→BA
=−−→OC−−−→BC−−−→AB
−−→OB=−−→OC+−−→CB=−−→OC−−−→BC
−−→CA=−−→CB+−−→BA=−−−→BC−−−→AB
Hence, option C.