Efficient Frontier Question

CFA Level II
#1

Schweser Practice Exam 3 Afternoon

Q109

Statement 2:A portfolio to the left of the efficient frontier is not attainable,while a portfolio to the right of the efficient frontier is inefficient

Above statement has been marked true as per answer. Can’t fully follow it, can someone explain? Why would portfolio to the right be inefficient?

#2

because just above it is a portfolio with same risk but better return

#3

A portfolio to the right of the efficent frontier would be inefficent because another portfolio exists with a higher return per unit risk.