Which organization is exempt from federal income tax under Section 501(c)(3)?

Cobra, Inc., a corporation, operated to advance the financial interests of its shareholders.

Amelia Hendricks Trust, a trust set up for the benefit of Amelia Hendricks' four grandchildren.

Reverend Tim Collins, a sole proprietorship, operated exclusively to advance a religious purpose.

Beakers and Test Tubes, Inc., a corporation, operated exclusively to advance scientific purposes.