Females have two copies of the X chromosome, while males have one X and one Y chromosome. The 22 autosomes are numbered by size. The other two chromosomes, X and Y, are the sex chromosomes. This picture of the human chromosomes lined up in pairs is called a karyotype.
Of the 23 pairs of chromosomes, the first 22 pairs are called "autosomes." The final pair is called the "sex chromosomes." Sex chromosomes determine an individual's sex: females have two X chromosomes (XX), and males have an X and a Y chromosome (XY).
The answer is A: a flagship species.
Hope this helps :)
To confirm the above hypothesis, Maria should perform an experiment to prove that xylem is responsible for the transport of coloured water through the plant. This is called the ascent of sap.
A suitable plant having a tender, semitransparent stem should be selected. The root system of the plant should be cut off and the twig has to be placed half-immersed in a coloured solution of water for about one hour. Later, when the plant is observed, parallely running streaks of coloured water can be seen through the semitransparent stem and other parts of the plant indicating that the xylem is involved in the upward movement of water.
