The particle gun method consists of which of the following steps?

 A. The DNA of interest is absorbed onto microprojectile beads

B. These beads are often made of aluminium

C. The explosion in a gun propels a macroprojectile forward which in turn propels microprojectile beads

D. The macroprojectiles and microprojectiles both cross the perforated plate and hit the target tissue behind it

Explanation: The DNA of interest is adsorbed on the microprojectile beads and these are made of gold and tungsten often. The explosion in the gun propels a macroprojectile forward and in turn propels microprojectile beads. These microprojectile beads cross the perforated plate but macroprojectiles don’t. The target tissue is behind the perforated plate and the microprojectiles hit it.