Answer
The right choices: (a), (b), (d) .
Work Step by Step
As a rule, a metal which is higher on the activity series can displace (reduce) of a metal which is lower from its salt.
a) Fe metal is higher than Ni on the activity series, so Fe(s) can reduce Ni²⁺ to Ni(s).
b) Tin metal is higher than lead on the activity series, so Sn(s) can reduce Pb²⁺ to Pb(s).
d) Lead metal is higher than platinum on the activity series so Pb (s) can displace of Pt²⁺ from its salt PtCl₂ (aq) and reduce it to Pt(s).
