Which of the following interhalogen compounds is not possible ?

Halogens react with each other to form a number of compounds called interhalogen compounds. Their genral formula is AX_(n) , where A is less electronegative halogen while X is a more electronegative halogen and n is its number. The interhalogen compounds are essentially covalent and more reactive than the halogens since the bond A-X is weaker than A-A or X-X bond. The reaction of interhalogens are similar to those of halogens. Which of the following interhalogen compound is not possible ?

Halogens react with each other to form a number of compounds called interalogen compounds. Their genral formula is AX_(n) , where A is less electronegative halogen while X is a more electronegative halogen and n is its number. The interhalogen compounds are essentially convalent and more reactive than the halogens since the bond A-X is weaker than A-A or X-X bond. The reaction of interhalogens are similar to those of halogens. Which of the following interhalogen compound is not possible ?

Which of the following interhalogen compounds is/are possible:

Which of the following is an interhalogen compound ?

Which of the following interhalogen compounds does not exist ?

Which of the following interhalogen is colourless