In general the glans of the penis. However it varies from man to man, for example some have sensitive nipples while others may have sensiteive testicles.
Penis
Science has proved that the nervous system is the least sensitive to radiation. Blood forming organs like marrow are the most sensitive.
It all depends on the organs. Those cells, tissues and organs, where theres lots of division are most sensitive to the harmful effects of radiation at high levels of exposure, including the skin, the gut mucosa, hair follicles and so forth...
Physically, it's usually the genitals -- primarily the testicles. These are the parts that hurt like heck if you kick a guy in the crotch. During sex though, it's the erect penis. Different parts of the penis are sensitive on different guys. For some of us, it's the underside, for others it's the tip. For some guys it's the very base of the penis, right where it joins the rest of the body. (There are exceptions, of course -- everybody's different.) Emotionally, a guy's most sensitive part is just like a girl's -- it's the heart. We're just more likely to hide the pain!
arm
if your health your brain
the neck is the most sensitive part of your body - WRONG The correct answer is your lip then thumb
clitoris
The eyes.
The most sensitive part on a woman's baby when giving a massage would be her neck. When massaging a woman's neck it takes away her stress.
Most probably her eyes because eyes are the most sensitive organ of the human body.
The skin is the most outer layer of the part of our body.In that case it is the most sensitive part of the body so its the first part of the body that can respond to stimuli
because your tongue is the most sensitive part of your body
Science has proved that the nervous system is the least sensitive to radiation. Blood forming organs like marrow are the most sensitive.
this is the most sensitive part of the body when the body is stimulated. the gee sport can arouse sexual feelings.
The Nipples are most sensitive.
Skin
All over your body but for the most part in males their belly-female-their thighs.