An element with Z = 77 of modern periodic table belongs to same group as that of the element with Z = 

detailed solution

Correct option is D

Hints to predict the position of element in the Modern periodic table :1)Elements from Z = 58-71……Lanthanoids…..4f series….6th period……3rd(IIIB) group;2)Elements from Z = 90-103……Actinoids…..5f series….7th period……3rd(IIIB) group;3)Elements from Z = 104-118………..Last two digits gives group number….. 7th period;4)Elements from Z = 31-57….subtract 18 to get preceding element;5)Elements from Z = 72-89….subtract 32 to get preceding element;6)Elements from Z = 104-120….subtract 32 to get preceding element ;For Z=104-120….simplest Hint7)Elements from Z = 104-120….subtract 82 to get a lower member(Z<30) belonging to same group;Hints 4, 5 and 6 can be used repeatedly until an element belonging to same group with Z < 30 is obtained;Elements with Z < 30 with their group, period and block can be known from Electronic configuration;Ex : Z=109, 77, 45, 27….belong to 9th(VIII) group;(109-32)=77; (77-32)=45; (45-18)=27;(n-1)d1-10ns1-2 ;Note : Many elements of d-block have anomalous configuration. So only GEC of each group is highlighted;Z = 27…….Co…  4s23d7…….n=4…..4th period…..d-block….…..9th group;Z = 45…….Rh………….….….n=5….5th period……d-block……...9th group;Z = 77…….Ir…………..………n=6….6th period……d-block…..…9th group;Z = 109…..Mt…………..……..n=7…..7th period……..d-block..……..9th group;