选择题
2020 AMC 8 Problem 21: Checkerboard Paths
A game board consists of 64 squares that alternate in color between black and white. The figure below shows square P in the bottom row and square Q in the top row. A marker is placed at P. A step consists of moving the marker onto one of the adjoining white squares in the row above. How many 7-step paths are there from P to Q?
2020 AMC 8 第 21 题：棋盘路径
游戏板由 64 个黑白交替的方格组成。下图显示底部行中的正方形 P 和顶部行中的正方形 Q。将标记放置在 P 处。步骤包括将标记移动到上一行中相邻的白色方块之一上。从 P 到 Q 有多少条 7 步路径
A.
28
B.
30
C.
32
D.
33
E.
35