Question: Who is the head of state of Germany who commanded the SM UC-25 minelaying submarine ?

Context paragraphs:
SM UC-25: SM "UC-25" was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: "Kaiserliche Marine" ) during World War I.  The U-boat was ordered on 29 August 1915 and was launched on 10 June 1916.  She was commissioned into the German Imperial Navy on 28 June 1916 as SM "UC-25".  In 13 patrols "UC-25" was credited with sinking 21 ships, either by torpedo or by mines laid.  March–September 1918 she was commanded by Karl Dönitz, later Grand admiral.  "UC-25" was scuttled at Pola on 28 October 1918 on the surrender of Austria-Hungary.

SM UC-41: SM "UC-41" was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: "Kaiserliche Marine" ) during World War I.  The U-boat was ordered on 20 November 1915 and was launched on 13 September 1916.  She was commissioned into the German Imperial Navy on 11 October 1916 as SM "UC-41".

SM UC-47: SM "UC-47" was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: "Kaiserliche Marine" ) during World War I.  The U-boat was ordered on 20 November 1915, laid down on 1 February 1916, and was launched on 30 August 1916.  She was commissioned into the German Imperial Navy on 13 October 1916 as SM "UC-47".  In 13 patrols "UC-47" was credited with sinking 56 ships, either by torpedo or by mines laid.  "UC-47" was rammed and depth charged by British patrol boat "P-57", under the command of H.C. Birnie, off Flamborough Head on 18 November 1917.  "UC-47" went down with all hands.

SM UC-42: SM "UC-42" was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: "Kaiserliche Marine" ) during World War I.  The U-boat was ordered on 20 November 1915 and was launched on 21 September 1916.  She was commissioned into the German Imperial Navy on 18 November 1916 as SM "UC-42".

Leninets-class submarine: The Leninets or L class were the second class of submarines to be built for the Soviet Navy.  They were minelaying submarines and were based on the British L-class submarine, HMS "L55" , which was sunk during the British intervention in the Russian Civil War.  Some experience from the previous "Dekabrist"-class submarine s was also utilised.  The boats were of the saddle tank type and mines were carried in two stern galleries as pioneered on the pre-war "Krab" , the world's first minelaying submarine.  These boats were considered successful by the Soviets and 25 were built in four groups between 1931 and 1941.  Groups 3 and 4 had more powerful engines and higher speed.

SM UC-62: SM "UC-62" was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: "Kaiserliche Marine" ) during World War I.  The U-boat was ordered on 12 January 1916, laid down on 3 April 1916, and was launched on 9 December 1916.  She was commissioned into the German Imperial Navy on 8 January 1917 as SM "UC-62".  In nine patrols "UC-62" was credited with sinking 12 ships, either by torpedo or by mines laid.  On 19 March 1917, the submerged Royal Navy submarine  suffered damage in a collision "UC-62" in the North Sea off the North Hinder Light Vessel.  "UC-62" struck a mine and sank in the North Sea off Zeebrugge, Belgium, on 14 October 1917.

Karl Dönitz: Karl Dönitz (sometimes spelt Doenitz) (] ; 16 September 1891 – 24 December 1980) was a German admiral who played a major role in the naval history of World War II.  Dönitz briefly succeeded Adolf Hitler as the head of state of Germany.

SM UC-24: SM "UC-24" was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: "Kaiserliche Marine" ) during World War I.  The U-boat was ordered on 26 August 1915 and was launched on 4 March 1916.  She was commissioned into the German Imperial Navy on 15 August 1916 as SM "UC-24".  In four patrols "UC-24" was credited with sinking 4 ships, either by torpedo or by mines laid.  "UC-24" was torpedoed and sunk by French submarine "Circé" off Cattaro on 24 May 1917.

SM UC-29: SM "UC-29" was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: "Kaiserliche Marine" ) during World War I.  The U-boat was ordered on 29 August 1915 and was launched on 15 July 1916.  She was commissioned into the German Imperial Navy on 15 August 1916 as SM "UC-29".  In an eight-month career, the "UC-29" performed seven combat patrols into the Atlantic Ocean during the German war on Allied trade ("Handelskrieg").  In these patrols she was very successful, sinking 18 allied ships, totalling 21,903 tons.  She also damaged 3 ships of 15,859 tons.  On 7 June 1917 she torpedoed the British Q-ship  off the Irish coast, but was ambushed by her hidden armaments when she approached too close and was sunk with 23 hands.  "Pargust" was commanded by British submarine hunter Gordon Campbell and had on board Ronald Niel Stuart and William Williams, who were awarded the Victoria Cross for their actions in the engagement.

SM UC-39: SM "UC-39" was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: "Kaiserliche Marine" ) during World War I.  The U-boat was ordered on 20 November 1915 and was launched on 25 June 1916.  She was commissioned into the German Imperial Navy on 31 October 1916 as SM "UC-39".  In one patrols "UC-39" was credited with sinking 3 ships, either by torpedo or by mines laid.  "UC-39" was forced to the surface by a depth charge attack and then sunk by gunfire from the British destroyer "Thrasher" off Flamborough Head on 8 February 1917.

Supporting paragraphs: SM UC-25 Karl Dönitz
Answer: Karl Dönitz