(a) A person commits an offense if, with specific intent to commit an offense, he does an act amounting to more than mere preparation that tends but fails to effect the commission of the offense intended.
(b) If a person attempts an offense that may be aggravated, his conduct constitutes an attempt to commit the aggravated offense if an element that aggravates the offense accompanies the attempt.
(c) It is no defense to prosecution for criminal attempt that the offense attempted was actually committed.
(d) An offense under this section is one category lower than the offense attempted, and if the offense attempted is a state jail felony, the offense is a Class A misdemeanor.