What is the central idea in the article The Disturbing History of Human Experimentation?

In the franz kafka’s the metamorphosis after gregory turns into a giant insect he realizes his sister grete can’t stand to look at him. he hides from his sister and stays under a bedsheet. what does this act suggest about gregor?

What to the slave is the fourth of july? by frederick douglass fellow-citizens—pardon me, and allow me to ask, why am i called upon to speak here to-day? what have i, or those i represent, to do with your national independence? are the great principles of political freedom and of natural justice, embodied in that declaration of independence, extended to us? and am i, therefore, called upon to bring our humble offering to the national altar, and to confess the benefits, and express devout gratitude for the blessings, resulting from your independence to us? but, such is not the state of the case. i say it with a sad sense of the disparity between us. i am not included within the pale of this glorious anniversary! your high independence only reveals the immeasurable distance between us. the blessings in which you this day rejoice, are not enjoyed in common. the rich inheritance of justice, liberty, prosperity, and independence, bequeathed by your fathers, is shared by you, not by me. the sunlight that brought life and healing to you, has brought stripes and death to me. this fourth of july is yours, not mine. you may rejoice, i must mourn. to drag a man in fetters into the grand illuminated temple of liberty, and call upon him to join you in joyous anthems, were inhuman mockery and sacrilegious irony. do you mean, citizens, to mock me, by asking me to speak to-day? fellow-citizens, above your national, tumultuous joy, i hear the mournful wail of millions, whose chains, heavy and grievous yesterday, are to-day rendered more intolerable by the jubilant shouts that reach them. if i do forget, if i do not faithfully remember those bleeding children of sorrow this day, "may my right hand forget her cunning, and may my tongue cleave to the roof of my mouth! " to forget them, to pass lightly over their wrongs, and to chime in with the popular theme, would be treason most scandalous and shocking, and would make me a reproach before god and the world. my subject, then, fellow-citizens, is american slavery. i shall see this day and its popular characteristics from the slave's point of view. standing there, identified with the american bondman, making his wrongs mine, i do not hesitate to declare, with all my soul, that the character and conduct of this nation never looked blacker to me than on this fourth of july. whether we turn to the declarations of the past, or to the professions of the present, the conduct of the nation seems equally hideous and revolting. what is one of the lessons douglass impresses on his listeners? a) the nation should not rejoice until everyone has freedom. b) he must speak on the fourth of july in order to bring change. c) for him to join the celebration would be treason. d) he can see the perspective of slaves and citizens with equal clarity.

Read this sentence: devon was nervous at the thought of speaking in front of a large audience. which word could a translator use to replace the underlined word without changing the meaning of the sentence? a. angry b. excited c. d. worried