( a ) growth, reproduction, ability to sense environment and mount a suitable response
( b ) growth, reproduction, ability to sense environment and mount a suitable response, metabolism, ability to self replicate, self organize, interact & emergence
( c ) growth, reproduction, ability to sense environment and mount a suitable response, mobility
( d ) growth, reproduction, ability to sense environment and mount a suitable response, mobility, metabolism, ability to self replicate, self organize, interact & emergence
