Investors are considering various short-term bond exchange-traded funds (ETFs) for their portfolios. The options being compared include Vanguard's VGSH, BSV, and VCSH, as well as iShares' IGSB and other ETFs such as SCHO, VTES, and SMB. The choice among these ETFs may depend on factors such as yield, costs, and investment goals, with some offering tax-exempt options or higher yields from corporate bonds.