A block is released from rest at the top of a frictionless inclined plane 16 m long. It reaches the bottom 4 sec later. A second block is projected up the plane from the bottom at the instant the block is released in such a way that it returns to the bottom simultaneously with first block. The acceleration of each block on the incline is

• A. \[\text{1 m}/{{\text{s}}^{\text{2}}}\]             
• B.         \[\text{2 m}/{{\text{s}}^{\text{2}}}\]  
• C. \[\text{4 m}/{{\text{s}}^{\text{2}}}\]             
• D.         \[\text{9}.\text{8 m}/{{\text{s}}^{\text{2}}}\]