Respuesta :

Answer:

Answer is A

Explanation:

so Redox reaction is when one element is getting reduced and other oxidized

if u getting confused what is Reduction and what is oxidation remember it as

OIL RIG ;- oxidation is losing of electron ..... reduction is gaining of electron

now,

       K is in free state so oxidation no is 0 and oxidation no of Ca is +2..... After the reaction K is Oxidized and Ca is Reduced