LIST - 1	LIST - 2
A) NH3	1) Oxidant
B) KMnO4	2) Both oxidant and reductant
C) SO2	3) Neither oxidant nor reductant
D) He	4) Reductant
	5) Dehydrating agent

The correct match is

NH₃
Ox. state of  nitrogen = -3
This is the least Ox. state of nitrogen(Group.No-8)

$\therefore$NH₃ can act like reductant but never act like Oxidant

KMnO₄
Ox. state of 'Mn' = +7
This is the highest Ox. state of 'Mn' (group.No)
$\therefore$KMnO₄  can act like oxidant but never act like reductant

SO₂
Ox. state of sulphur = +4
This is the intermediate Ox. state of sulphur (between - 2 & +6)
$\therefore$SO₂ can act like both oxidant (Or) reductant

He
Neither oxidant nor reductant