My aunt would rather __________a bus _________ride a bike.

A． to take, than

B． take, to

C． take, than

D． taking, than

已知抛物线C的顶点在原点，焦点为F（1，0），且过点A（t，2）．

（1）求t的值；

（2）若直线y=kx-1与抛物线C只有一个公共点，求实数k的值．