What does line 73-94 talking about

we know that, volume of a rectangular prism is given by :

✿   {length × width × height}

given : the length of rectangular prism = 5.5

given : the width of rectangular prism = 6

given : the height of rectangular prism = 3

⇒ the volume of given rectangular prism = {5.5 × 6 × 3}

⇒ the volume of given rectangular prism = 99

the answer is c because info security should not use them for code

it is an infinitive phrase with a subject.