When blood pressure increases:
a. norepinephrine secretion increases.
b. baroreceptors detect the change in the carotid arteries.
c. the cardioregulatory center decreases parasympathetic stimulation of the heart.
d. heart rate and stroke volume increase.

a. norepinephrine secretion increases.

Explanation:

Norepinephrine (NE), is an organic chemical in the catecholamine family that performs the role of neurotransmitter in the brain and in the body it functions as hormone. Norepinephrine affects the way the brain pays attention and responds to events, it can increase heart rate, trigger the release of glucose (sugar) into the blood , Increase blood flow to muscles.

Let consider a case of a fight-flight response scenario, where blood level increases, as such:

Norepinephrine will also increases arousal and alertness, promotes vigilance, enhances formation and retrieval of memory, and focuses attention. In the rest of the body, it  will increases heart rate and blood pressure.

answer: angiosperms

dicots

angiosperms are highly evolved plants, they produce seeds which are enclosed within in a carple. these are the largest group of plants on earth. they include trees, shrubs, herbs and small flowering plants. angiosperms exhibit a flowering stage in their life cycle. the flower serves the function of reproduction and fruit formation in majority of angiosperms. dicot is the term used to describe flowering plants that have two seed leaves. dicots are plants which develop seeds which split into two parts called cotyledons. each cotyledon contains one embryo.

here, a small purple flower development indicates that the plant belongs to angiosperms and having two embryonic leaves indicates it belongs to dicots.