[单选题]
A positive point chargliem-f;zi *p01-zka a e is ez-f aat*6nho9 nclosed in a hollow metallic sphere that is grounded. As compared to the case without the hollow sphere, the electric field at a point diratn69-*ahfz o ectly above the hollow sphere has
A. diminished to zero.
B. diminished somewhat.
C. increased somewhat.
D. not changed.
