Which sequence correctly lists the four strokes of a typical four-stroke engine?

• A. Induction(down) 2. Compression(up) 3. Power(expansion) (down) 4. Exhaust (up).
• B. Intake, Exhaust, Combustion, Compression.
• C. Compression, Induction, Exhaust, Power.
• D. Exhaust, Induction, Compression, Power.

Answer: (A)

Understanding the order of the four strokes in a typical four-stroke engine. The cycle goes in this exact sequence: induction (intake) with the piston moving downward to draw the air-fuel mixture into the cylinder, then compression with the piston moving upward to compress that mixture, followed by the power (expansion) stroke where the mixture burns and pushes the piston downward, and finally the exhaust stroke with the piston moving upward to expel the exhaust gases. The correct option matches this order and the associated piston directions: induction down, compression up, power down, exhaust up. Other sequences mix up these steps (for example, starting with compression or exhaust would not properly draw in or expel gases at the right times), which is why they’re not correct.