Contraindications to aspirin are all; EXCEPT: 
a. Peptic ulcer                      b. Bleeding tendencies 
c. Chicken pox                     d. Rheumatoid Arthritis 

The correct answer is d. Rheumatoid Arthritis.

Aspirin is a commonly used medication that belongs to a class of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). It is widely used for its anti-inflammatory, analgesic (pain-relieving), and antiplatelet (blood-thinning) properties. However, there are certain contraindications, which means situations or conditions in which it is not recommended to use aspirin.

a. Peptic ulcer: Aspirin can irritate the lining of the stomach and increase the risk of developing a peptic ulcer or worsen an existing ulcer. Therefore, it is contraindicated in individuals with active peptic ulcers.

b. Bleeding tendencies: Aspirin has an effect on platelets, which are small cells responsible for blood clotting. It reduces the ability of platelets to stick together, which can increase the risk of bleeding. Therefore, it is contraindicated in individuals with bleeding disorders or those who are at high risk of bleeding, such as individuals with a history of bleeding disorders or those taking anticoagulant medications.

c. Chickenpox: While chickenpox itself is not a contraindication to aspirin, it is recommended to avoid giving aspirin to children or teenagers who have chickenpox or flu-like symptoms. This is because aspirin use during these viral infections has been associated with the development of a rare but serious condition called Reye's syndrome, which affects the liver and brain.

d. Rheumatoid Arthritis: Rheumatoid arthritis is not a contraindication to aspirin. In fact, aspirin is commonly used as an anti-inflammatory medication to relieve pain and inflammation associated with rheumatoid arthritis.

It is important to always consult a healthcare professional or follow the recommendations on the medication label before using aspirin or any other medication to ensure its appropriate and safe use.