What are my options on rental agreement ?

i and my friend(A) signed a lease for an apartment in California(Bay Area) on last April. When we signed the lease, we clearly told the broker of the apartment that there will be three people living in the apt and also asked him if the third person(B) also needed to sign the lease. He told us that we would be fine without the third person(B) signing the lease. In a month, the other lease-holder(A) moved out and he was replaced by another friend(C). Now after a month, he came to our apt and asked us to pay an extra 100 dollars for the new roomate(C) we had or either he(C) had to leave.(all utilities exp sanitary are paid by us) He also wanted us to sign a new lease with increased rent, under our name(B,C and me).Now he denies that we told him that three persons were living, when we signed the lease. We are financially broke, so we can’t afford the rent by 2 persons(me and B) or pay extra 100 for the third person(C). What are my options on rental agreement ? Can I break the lease without getting in trouble? Can he increase the rent in the middle of lease?

Please give us some advice.

Thanks.