How is the line transect technique carried out​

A line transect is carried out by unrolling the transect line along the gradient identified. The species touching the line may be recorded along the whole length of the line (continuous sampling). Alternatively, the presence, or absence of species at each marked point is recorded (systematic sampling).

answer; i believe that the correct answer is (c) arctic tundra;

there is no chart here so no one can answer this.