Was the Christian story borrowed from other pagan religions?

Osiris

The cult of Isis believed the "god" Osiris was supposedly murdered by his brother and buried in the Nile. The goddess Isis recovers the cadaver, only to lose it once again to her brother-in-law who cuts the body into 14 pieces and scatters them around the world. After finding the parts, Isis “baptizes” each piece in the Nile river and Osiris is “resurrected.”  The parallels between the “resurrection” of Osiris and the resurrection of Christ are an obvious stretch  [ 1 ]

Mithraism

Mithraism is another pagan religion. Mithra was supposedly born when he emerged from a rock. He was carrying a knife and torch and wearing a Phrygian cap. He battled first with the sun and then with a primeval bull, thought to be the first act of creation. He slew the bull, which then became the ground of life for the human race. Mithra was considered the son of God. He was a savior. He was born of a virgin and had 12 disciples. He was crucified. He rose from the grave on the third day.. He atoned for the sins of humankind. He returned to his father in heaven. However, this cult flowered after Christianity, not before. The timing is all wrong to have influenced the development of 1st Century Christianity. [ 2 ]

Cited Sources: [1] The Complete Bible Answer Book by Hank Hanegraaff, [2] Baker Encyclopedia of Christian Apologetics by Norman Geisler