An alternative with normal formulas (not array ones) but with a volatile function as well (SUMPRODUCT):
=INDICE(A2:B6;SUMAPRODUCTO((A2:A6=A2)*(B2:B6=MAX(B2:B6))*FILA(B2:B6))-1;2) -----> in english: =INDEX(A2:B6,SUMPRODUCT((A2:A6=A2)*(B2:B6=MAX(B2:B6))*ROW(B2:B6))-1,2)