In The Day of the Triffids, after most people in the world are blinded by an apparent meteor shower, an aggressive species of alien plants (brought to earth on the meteors) starts attacking people. Some Triffids have a poison stingers, and some do not. A true breeding strain of Triffids with poison stingers is crossed with a true breeding strain of Triffids with no stingers. All of the progeny have poison stingers. Which trait is dominant