Sometimes a subject may be more than one thing or person. They have more than one noun or pronoun and are called compound subjects.
Debra, Harry, and I watched the movie.
Here, there are three main subjects “.” These three form a compound subject.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
The correct answer is
The smallest number is the one that comes first while counting.
To arrange the given numbers in order from smallest to greatest, find the smallest number among all the given numbers.
21 is the smallest number.