A furniture store sells kits that customers use to build cabinets. Each kit contains 18 screws and a set number of boards. Jarred buys 6 of these kits and has a total of 192 screws and boards. He writes the equation shown to represent the situation.

6(x + 18) = 192
What does the varaible X represent in Jarred's equation?
(1 point)
The number of screws in 1 kit
The number of screws in 6 kits
The number of boards in 1 kit
The number of boards in all 6 kits