Which statements about the gated recurrent unit $($GRU$,$ Cho et al$.,2014)$ are true?

a$.$ The GRU has less parameters than an LSTM without forget gate that has the same number of hidden units.

b$.$ The so$-$called "update gate" of the GRU acts as a coupled input and forget gate.

c$.$ The GRU has one gate more than the fully featured LSTM architecture.

d$.$ A forget gate mechanism is the core of the GRU architecture.

e$.$ In the GRU, a so$-$called "reset gate" $r(t)$ regulates how strongly the increments $z(t)$ depend on the old hiddens $h(t-1).$