Answer:
72.0 mL of steam is formed.
Explanation:
The reaction is :

You can treat coefficient of compounds as amount of volume used.
Therefore for 4 mL of ammonia 5 mL of oxygen is used to form 4 mL of nitric oxide gas and 6 mL of steam.
For 1 mL of ammonia
(=1.25) mL of oxygen is used to form
(=1) mL of nitric oxide gas and
(=1.5) mL of steam.
OR
Just transform the chemical equation by dividing the whole equation by 4 so that the coefficient of
become one like this

We don't know which one will be completely exhausted and which one will be left so we have to consider two cases :
<em>1. </em><em>Assume ammonia to be completely exhausted</em>
For 50 mL of ammonia
(= 62.5) mL of oxygen is needed. But we have just 60 mL of oxygen so this assumption is false.
2. <em>Assume oxygen to be completely exhausted</em>
For 60 mL of oxygen only
(=48) mL of ammonia is needed. In this case we have sufficient amount of ammonia. So this case is true.

Now we know that during complete reaction 48 mL of ammonia and 60 mL of oxygen is used which will form
(= 48) mL of nitic oxide gas and
(= 72) mL of steam.
Therefore <em>72 mL of steam </em>is formed.
As you have not provided the options, still we can figure out the answer by understanding the key difference between saturated and unsaturated hydrocarbons.
SATURATED HYDROCARBONS are those hydrocarbons which only consist of a carbon carbon single bonds. All the bonds are sigma there are no pi bonds at all. Examples are shown below.
While, UNSATURATED HYDROCARBONS are those hydrocarbons which may contain either a double bond or triple bonds or both of them between the carbon atoms as shown below.
The smallest functional and structural unit of an organism, usually microscopic and consisting of cytoplasm and a nucleus in a membrane.