Syntax for unless conditional statement is

unless conditional [then]
   code
else
   code 
end

A. case B. while C. for D. if

A. while B. until C. for D. do...while

A. Executes code if condition is true B. Executes code if condition is false C. Breaks out of loop if condition is true D. Executes code only once if condition is true

A. To define a class B. To handle multiple conditions with one expression C. To declare a variable D. To perform mathematical calculations