Bond ETFs are similar to other ETFs (Exchange Traded Funds). Bond ETFs pay out interest through a monthly dividend, while any capital gains are paid out through an annual dividend. For tax purposes these dividends are treated as either income or capital gains. However, the tax efficiency of bond ETFs is not a big factor because capital gains do not play as big of a part in bond returns as they do in stock returns. Bond ETFs are available on a global basis. Barclays Global Investors, for example, has created ETFs that are available in the U.S., Europe and Canada.
Naked options trading is very risky - many people lose money trading them. It is recommended contacting your broker or investment professional to find out about trading risk and margin requirements before getting involved into trading uncovered options.