As a card is drawn from a deck of 52 cards 

Let S denotes the event of card being a spade and K denote the event of card being King. 

As we know that a deck of 52 cards contains 4 suits (Heart ,Diamond ,Spade and Club) each having 13 cards. The deck has 4 king cards one from each suit. 

We know that probability of an event E is given as-

P(E) = \(\frac{number\,of\,favourable\,outcomes}{total\,number\,of\,outcomes}\)   = \(\frac{n(E)}{n(s)}\)

Where n(E) = numbers of elements in event set E 

And n(S) = numbers of elements in sample space. 

Hence,

P(S) =  \(\frac{n(spade)}{total\,number\,of\,cards}\) =  \(\frac{13}{52}=\frac{1}{4}\) 

P(K) = \(\frac{4}{52}=\frac{1}{13}\)

And P(S∩K) = \(\frac{1}{52}\)

We need to find the probability of card being spade or king, i.e.

P(Spade ‘or’ King) = P(S∪K) 

Note: By definition of P(A or B) under axiomatic approach(also called addition theorem) we know that: 

P(A∪B) = P(A) + P(B) – P(A∩B) 

∴ P(S∪K) = P(S) + P(K) - P(S∩K) 

⇒ P(S∪K) = \(\frac{1}{4}+\frac{1}{13}-\frac{1}{52}\) 

= \(\frac{17}{52}-\frac{1}{52}\) = \(\frac{16}{52}=\frac{4}{13}\)

∴ P(S∪K) = 4/13 

∴ Option (c) is the correct choice.