Which Technique Below Describes Ouchterlony Double Diffusion

Multiple Choice

Which technique below describes Ouchterlony double diffusion?

A) Antibodies are added to liquid agarose, and the agarose is allowed to harden. Holes are cut in agarose, and specimens are placed in the holes. The specimens diffuse out of their wells, forming precipitin rings.
B) Antibodies are added to liquid agarose, and the agarose is allowed to harden. Holes are cut in agarose, and specimens are placed in the holes. The agarose is placed in an electrical field, and the specimens migrate out of their wells, forming precipitin lines.
C) Holes are cut in agarose. Antibodies are placed in one well, and a specimen is placed in the other well. The agarose is placed in an electrical field, and the antibodies and specimen migrate out of their wells, meeting in the middle, forming a precipitin line.
D) Holes are cut in agarose. Antibodies are placed in one well, and a specimen is placed in the other well. The antibodies and specimen diffuse out of their wells, meeting in the middle, forming a precipitin line.