A project has the timing illustrated by the following cash flow diagram:

Which of the following statements about this cash flow diagram is correct?

a$.$ Year $1$ ends at point $2$ and year $2$ begins at point $B.$

b$.$ Year $1$ ends at point A and year $2$ begins at point $B.$

C$.$ A project has four periods.

d$.$ Year $1$ ends at point $2$ and year $2$ begins at point $2.$

e$.$ First cost should be put at point $1.$