JEE Main 2002 Chemistry question

Arrange , , and in increasing order of their ionic radii

• (1)Yb^{+3} < Pm^{+3} < Ce^{+3} < La^{+3}Correct
• (2)Ce^{+3} < Yb^{+3} < Pm^{+3} < La^{+3}
• (3)Yb^{+3} < Pm^{+3} < La^{+3} < Ce^{+3}
• (4)Pm^{+3} < La^{+3} < Ce^{+3} < Yb^{+3}