Question: What objects were carried into battle by these naval ships for qhich the QF 6-pounder Hotchkiss were introduced to defend against?

Passages:
The "Male" tank was a category of tank prevalent in World War I.  As opposed to the five machine guns of the female version of the Mark I tank, the male version of the Mark I had a QF 6 pounder 6 cwt Hotchkiss and three machine guns. By the end of World War I, tank technology was advanced enough for tanks to be both male and female. The Ordnance QF 75 mm, abbreviated to OQF 75 mm, was a British tank-gun of the Second World War.  It was obtained by boring out the Ordnance QF 6 pounder ("6 pdr") 57-mm anti-tank gun to 75-mm, to give better performance against infantry targets in a similar fashion to the 75mm M3 gun fitted to the American Sherman tank.  The QF came from "quick-firing", referring to the use of ammunition with the shell and propellant in a single cartridge.  The gun was also sometimes known as ROQF from Royal Ordnance (the manufacturer) Quick-Firing. The Ordnance QF 6-pounder 6 cwt Hotchkiss Mk I and Mk II was a shortened version of the original QF 6 pounder Hotchkiss naval gun, and was developed specifically for use in the sponsons of the later Marks of British tanks in World War I, from Mark IV onwards. The Ordnance QF Hotchkiss 6 pounder gun Mk I and Mk II or QF 6 pounder 8 cwt were a family of long-lived light 57 mm naval guns introduced in 1885 to defend against new, small and fast vessels such as torpedo boats and later submarines.  There were many variants produced, often under license which ranged in length from 40 to 58 calibers, but 40 caliber was the most common version. The Ordnance QF 3-pounder Vickers (47mm / L50) was a British artillery piece first tested in Britain in 1903.  It was used on Royal Navy warships.  It was more powerful than and unrelated to the older QF 3-pounder Hotchkiss, with a propellant charge approximately twice as large, but it initially fired the same Lyddite and steel shells as the Hotchkiss. A torpedo boat is a relatively small and fast naval ship designed to carry torpedoes into battle.  The first designs rammed enemy ships with explosive spar torpedoes, and later designs launched self-propelled Whitehead torpedoes.  They were created to counter battleships and other slow and heavily armed ships by using speed, agility, and the power of their torpedo weapons.  A number of inexpensive torpedo boats attacking en masse could overwhelm a larger ship's ability to fight them off using its large but cumbersome guns.  An inexpensive fleet of torpedo boats could pose a threat to much larger and more expensive fleets of capital ships, albeit only in the coastal areas to which their small size and limited fuel load restricted them. The QF 3-pounder Hotchkiss or in French use Canon Hotchkiss à tir rapide de 47 mm were a family of long-lived light 47 mm naval guns introduced in 1886 to defend against new, small and fast vessels such as torpedo boats and later submarines.  There were many variants produced, often under license which ranged in length from 32 to 50 calibers but 40 caliber was the most common version.  They were widely used by the navies of a number of nations and often used by both sides in a conflict.  They were also used ashore as coastal defense guns and later as an anti-aircraft gun, whether on improvised or specialized HA/LA mounts. The QF 14 pounder was a 3-inch medium-velocity naval gun used to equip warships for defence against torpedo boats.  It was produced for export by Maxim-Nordenfelt (later Vickers, Sons and Maxim) in competition with the Elswick QF 12-pounder 12 cwt and QF 12-pounder 18 cwt guns. The Ordnance QF 2-pounder (QF denoting "quick firing"), or simply "2 pounder gun", was a 40 mm British anti-tank and vehicle-mounted gun, employed in the Second World War.  It was actively used in the Battle of France, and during the North Africa Campaign.  As Axis tanks improved in armoured protection, it lost effectiveness, and it was gradually replaced by the 6-pounder, starting in 1942, though some remained in service until the end of the war.  In its vehicle-mounted variant, the 2-pounder was also a common main gun on British tanks early in World War II, and was a typical main armament of armoured cars, such as the Daimler, throughout the war. The QF 6 inch Gun Mark N5 (initially designated QF 6 inch Mk V) was a British naval gun, which was developed in the post-war period.  It was the last large gun to be operational with the Royal Navy.

Supporting sentences:
A torpedo boat is a relatively small and fast naval ship designed to carry torpedoes into battle.  The first designs rammed enemy ships with explosive spar torpedoes, and later designs launched self-propelled Whitehead torpedoes.