Am I right to say that PES C MOs are only given the rank of LTA and are Nursing Officers?
Yeah, I heard something like that too. But it's supposed to apply only to reservists, or to those who'd gotten their medical degrees after serving in another vocation during NS?
Most MOs are CPTs, the difference being their commissionings are obtained after finishing MOCC rather than OCS.
and lastly...if a WO sees a jr commisioned officer, mus he/she salute?
Yes, if their paths crossed outside & they didn't know each other. In the unit or the camp itself, unit appointments play as much a role. A conscripted 2LT mustn't blatantly pull rank on, say, a regular RSM. I mean, the latter can't refuse obeying a direct order from the junior officer, but he can go up his own proper COC to the CO to see redress.